Automatic work feeder



ATTORNEY.

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WTA/5555 A TTORNE Y.

Patented June 5, 1923.

UNTED STATES REGINALD B. GERHARDT, 0F SPARBOWS POINT, IMAZBFYLAISI'D.

AUTOMATIC 'WORK FEEDER.

Application filed August 18, 1921. Serial No. 493,480'.

To all wkomz'tmy concern."

Be it known that I, REGINALD B. GER- HARDT, a citizen ofthe UnitedStates, residing at Sparrows Point, in the county of Baltimore and Stateof Maryland, have invented a new and useful Automatic' Work Feeder, ofwhich the following is a specification, the accompanying drawingsforming a part of the same.

My invention relates to improvements in automatic work feeders forsheets of any magnetic material in which reciprocating vacuum liftersoperate in conjunction with rotating electromagnets; and the objects ofmy improvements are first, to provide a means to separate the work forfeeding individual sheets and second to afford facilities for properadjustment of feed table, vacuum lifters and electromagnets for theautomatic feeding of Work to a forming or other machine.

I attain these objects by the mechanism illustrated in the accompanyingdrawings in which- Figure 1 is a vertical front elevation of the entiremachine partly in section. Fig. 2 is a vertical end elevation. Fig. 3 isa vertical section of the machine on line A--B, Fig. 1. Fig. 4 isalvertical sectional view on line C--D, Fig. 1. Fig. 5 is a verticalsection on line E-F, Fig. 1. Fig. 6 is an enlarged section on line(ir-H, Fig. 1. Figs. 7 and 8 are diagrammatic views of the electricalcircuits for the controlling of the operating of my automatic workfeeder.

Similar numerals refer to similar parts throughout the several views.

Referring more particularly to the drawings, the device comprises a base1, standards 2 and a top plate 3 which form the main frame for thedevice.

Secured to the top plate 3 is an ,electric driving motor 4 which isprovided with a shaft on which 'is mounted a pinion 5.

a Mounted on each end of the top plate 3 is a journal box 8, whichjournal boxes support a drive shaft 7, the latter provided with a ear 6which meshes with pinion 5. I

he numeral 13 designates a cross guide which is mounted forreciprocatory move-- ment in channel bars 14 formed integral withstandards 2. To impart a reciproca-v tory movement to the crossguide 13,each end thereof is pivotally connected to a connecting rod 11, by meansof a pin 58 yextending through a right angular portion formed on shaftvintegral with said rod 11 and extending through an aperture \12 instandard 2. The upper end of connecting rod 11 is pivotallandeccentrically secured to a crank dis 9 formed on each end of shaft 7,a pin 10 retaining rod 11 and disk 9 in connected relation.

Cross guide 13 is provided with a plurali'ty of apertures for thereception o picker arms or sheet lifters. The picker arms each comprisea tube 18 which terminates in a vacuum cup 16, secured to said tube by aclamping band 17 or the like. The numeral 20 denotes a valve rod havinga head 21 lwhich is adapted to seat agamst valve seat 19 in suction cup21. The end of valve rod 20 extends beyond the tube 18 and is providedwith a collar 24 secured thereto by a set screw 25. The end of tube 18is provided with a collar 22 and positioned on rod 20 between collars 22and 25 is a coil spring 27. Near the lower end of tube 18 is a collar 23and a coil spring 26 is positioned on thetube 18 between said collar 23and cross guide '13, Secured to the top plate 3 above each of thelifters is a regulating screw 15.

The numeral designates a -vertically movable feeding table for thesheets 62. In some instances it may be desirable lto feed the sheetsfrom a liquid, and to this end a box 61 is provided as shown clearly inFig. 1.

The electromagnets associated with this device, are keyed to a shaft 72,which is revolved in journals 8O fastened to standards 2. Shaft 72 isrotated by means of a friction gear mechanism, being driven from maindriving shaft 7 on which is keyed a spiral gear 63 whichl meshes with amating gear-64 keyed on shaft 65 which latter revolves in bearings 66and 67 fastened to top plate 3 and bar 68 respectively. In the lower endof shaft there is a long key for the driving of a pinion-70 which latterbears against the face of a friction disc 71, keyed 72 and so rotatesshaft 72 and all parts keyed or fastened to said shaft. There will betimes when the size of sheets to be fed to the forming or other machinewill necessitate a change in speed of delivering the sheets from thevelectromagnets to the pinch rolls and to accomplish this, I provide oneach side of 70 a collar 69 held at an adjustable location by a setscrew to give the redetermined speed from friction pin# ion 0 to theelectromagnets.

The electromagnets, one of which islshown in section in Fig. 1 areconstructed with a cylindrical shell 73 of soft iron material keyed toshaft 72and with a threaded hub end 76 for the holding of flange 74 ofsoft iron material. The internal periphery of 73 and 74 is curved asshown at 79 in Fig.l 1 to confine the magnetic field in an outwarddirection from center of the electromagnets or to the sheets beinglifted and the threaded end 76 is provided as a, means to regulate thestrength of the magnetic influence for lifting different weights ofsheets by turning ange 74 on thread 76 thereby narrowing or widening thespace between 73 and 74 at periphery 79 and @hangin the magnetic inuenceto suit weights o sheets being lifted. The copper wire 77 for conductingof electric current to the end of outwardly cylindrical walls of shell73 and flange 74 at 79, which are the poles of the electroma ets, iswound spirally around the hub o shell 73 and within the insulated casing75. The two ends of said wire pass through insulated bushings 78 aiXedto shell 73, and are guided by bands 100 on shaft 72 to collector rings90 on collar 89 keyed to sha-ft 72. Collar 89 is grooved as shown insection at 91, Fig. 5 for passage of electric current conducting wiresfrom collector rings 90 on which bars 92, fastened to insulated block 93on a bar 68, bear to trans mit the electric current to theelectromagnets through wires 99a and 99b from knife switch 99c shown inFig. 7.

At Fig. 4 is shown a sectional view of the top part of one of thelifters to which has been applied a means whereby the pile sheets ofsheets 62 will be kept at ,the proper level to be within ran e of thedownward 'travel of the lifters as te ile of sheets diminishes in heightdue to fee ing to forming or other machine.

On the downward stroke of the lifters if sheets 62 are so low in heightof pile that contact lingers 28, which ride loosely on insulatedcylinder 30, touch 31 fastened to one of the standards 2 at insulatedwasher 32, an electricA circuit is completed to electric solenoid 33fastened to one of the standards 2 by supports 34, through wires 33",33, 33d and knife switch 33". At the instant the electric circuit ismade, the solenoid core 35 which is extended to lever 36 and held'to thesame by the pin 37, is then ulled up by magnetic field of solenoid 33aever 36 being fulcrumed at pin 38 to one of the standards2, imparts adownward movement to ratchet pawl 39 at pin 40 until the vratchet pawlen ges teeth 46 of a ratchet wheel keye to elevating screw 50. Ratchetpawl 39 is given a reciprocating movement by lever 41, which is attachedby v pin 42 to the pawl 39 and by pin 44 to an eccentric lever 43 keyedto one end-of shaft 72. The screw is revolved in bearings 49 and 53 onone side of the feeder. The elevating screw 51 on the other side of theframe is similar to screw 50 except there is no extended end for aratchet wheel and said screw 51 is rotated by means of miter gears 54and shaft -55 which latter revolves in bearings 56 in standards 2. Thehelical threads of screws 50 and 51 engage internal threads in bearings52 which are bolted to elevating table 60 guided in movements bystandards 2 and in the revolving of these elevating screws the threadson said screws raise or lower the table 60 according to the direction ofrotation of the screws. As an auxiliary for the rapid movement of table60 there is provided on one end of shaft 55 a square end 57 for thereception of a hand crank or power wheel.

At F ig. 6 is shown an enlarged section of a dashpot for retarding therapid withdrawal of pawl 39 from teeth 46 on ratchet wheel 45 giving aprolonged movement to wheel and so act .against a counterweight 47fastened to lever 36 by pin 48. The function of the counterweight 47 isto withdraw lever 39 from engaging teeth 46 after solenoid electriccircuit has been broken when the sheets 62 have reached the properheight to be within the range of the downward stroke of the litters. Thedashpot consists of acylinder closed on the bottom as shown in Fig. 6.On the end of an extension 35a to solenoid core 35, there is held byscrew 98 a piston head 95 provided with a washer 97 said piston headworking in dashpot 94. In t-he upward stroke of core 35 due to anelectric circuit at solenoid being completed by contact fingers 28touching bars 32' as above described, air will flow through openings 96in piston head 95, the pressure of the inlowing air bendin resilientwasher 97 away from face of 'piston head, equalizing the air preure oneach side of same but in the downward stroke of core 35 upon thebreaking of the solenoid electric circuit, washer 97 is forced againstface of piston head 95, closing openings 96 and causing a retardeddownward movement by reason of air cushion in bottom of cylinder 94thereby giving a delayed withdrawal of pawl 39 in teeth 46. In otherwords, the washer 97 acts as an automatic valve.

The lifters or picker arms are lowered by means of cross guide 13 beingforced downwardly by connecting rod 11, in an obvious manner, the valvehead 21 seating at 19 in cup 16. The cups engage one of the sheets 62 inthe usual manner and upon raisingof the cross guide 13 the sheet iselevated until it is seized by the electromagnets, and substantiallysimultaneously the set screw`15 forces valve head 18 in a downwarddirection, thus unseating valve head ,22 from seat 19, breaking thevacuum in cup 16.

lll() lis with a gear 82 which receives a sprocket chain 83 which chainis driven by a larger I"gear 81 keyed to a shaft 72. It is obvious 'thatas shaft 72 is rotated, ,the pinchl rolls 84 and 84a will be rotated dueto gears 81 and 82 and chain 83.

Thile the sheets 62 will normally be fed directly from off the table 60,there will be times when, due to the class of work being performed onsaid sheets, that they shoul be fed from a box of liquid, and to providefor this an open box 61 is placed on the table and the sheets liftedfrom said box.

At Fig. 7 is shown diagrammatically the vmethod of controllingelectrically the starting and stopping of movements of the feeder. Knifeswitch 101 is provided for closing the electric circuit to the drivingmotor 4c through wires 102, 102", 102, 1021, 102e, switch I102f andrheostat 102g, the latter for controlling the electric current in theusual manner. For the purpose of automatically stopping the device whenall of the sheets 62 have been removed from the table 60, a pro.liection 59. formed on one bearing 52 of table 60 is provided. rIheautomatic elevation of table 60 has been hereinbefore described, andwhen said table has reached its maximum height, the projection 59 willopen a switch 102f thus breaking the circuit through the main controlswitch 101 (see Fig. 7 and stopping the entire device.

As the feeding of sheets to forming or other machine is entirelyautomatic there is provided an alarm-bell 103 as shown in Fig 8 to givewarning of the diminishing number of sheets on tablefor in box by meanslof projection 59 closing the electric circuit through wires 105a and105b from battery 104 in lifting handle 107 of switch 106 as theelevating table is raised by screws 50 and 51.

Having described my invention what claim is 1. A sheet feeding anddelivering machine comprising a frame, a vertically movable feed table,a plurality of picker elements, means on said frame for reciprocatingsaid picker elements, rotary magnetic means for receiving sheets fromsaid picker elements, adjustable means for releasing a sheet from saidpicker elements simul- 'taneously with the receipt of said sheet by saidrotary magnetic means, means lfor rotating said rotary magnetic meanswhereby a sheet is moved horizontally, and pinch rolls adapted to removesaid sheet from said rotary magnetic means.

2. A sheet feeding and delivering machine i comprising a frame, avertically movable feed table, a plurality of pneumatic picker elements,means on said frame for reciprocating said picker elements, variablerotary magnetic means for receiving sheets from said picker elements,-means whereby said magnetic means may be rotated at varying speeds,variable means for releasing a sheet .pal

from the picker elements, androlls adapted to receive a sheetl forconveyance from said magnetic means. f

rotary 3. n a sheet feeding and delivering device a frame, a sheetfeeding table, a motor, a.

cross guide, a plurality of pneumatic picker elements actuated by saidcross guide, means connecting said motor and cross guide for actuatingthe latter, a plurality of rotary electro-magnets, means for varying thestrength of magnetic influence of each of said electro-magnets, variabledriving connections from said motor to said electromagnets, means forautomatically elevating said sheet feeding table, and means forprolonging the elevating movement of 'said sheet feeding table.

4. In a sheet feeding and delivering device, having a frame, thecombination with a driving motor, pneumatic picker elements, rotatingelectro-magnets for receiving sheets from said picker elements, drivingconnections between said motor and said picker elements and rotatingeleotro-magnets, of a sheet feeding ta-ble, connected elevating screwsfor said feeding table, a rack on one of said screws, a solenoid securedto the frame, circuit making means on one of the before-mentioned pickerelements connected to said solenoid, a lever pivoted to said frame andprovided with a counter-weight at the free end thereof, a pawl securedto the opposite end of said lever and adapted to be lowered intoengagement with the beforementioned rack, a crank for reciprocating saidpawl, a solenoid core pivotally secured to the before-mentioned leverand provided with an extension, a piston head secured to said extensionand provided with valve means thereon, anda cylinder for said pistonhead. v

5. In a sheet feeding and delivering device having a frame, thecombination with a driving motor, pneumatic picker elements, rotatingelectro-magnets for receiving sheets from' said picker elements, drivinoonnections'between said motor, picker e ements, and rotatingelectro-magnets, of a` sheet feeding table, a solenoid secured to theframe and provided with a core, means secured to one of the dpickerelements for' energizing said solenoi means connected to said core forelevating said sheet feeding table, and means also secured to said corefor retarding the withdrawal of said core from said solenoid.

6. A sheet feeding and delivering device comprising a frame, a motor, aplurality of suction picker elements, means connected to said lnotor forreciprocating said picker elements, adjustable means for releasin thesuction of said picker elements, a plurality of rotary, variable,electro-magnets adapted to receive a sheet following its elevation bysaid picker elements, an adjustable driving connection from said motorto said electromagnets, a sheet feeding table, and'means operable by oneof said picker elements for elevating said sheet feeding table.

7.- A sheet feeding and delivering device comprising` a frame, a drivingmotor, a vertically movable sheet feeding table, a plurality of rotaryelectro-magnets, means for varying the strength of magnetic influence ofeach of said electro-magnets independently of the current appliedthereto, a plurality of vertically movable pneumatic picker elements forlifting sheets individually from said feeding table to saidelectro-magnets, and means rotatable by said motor for entirely removingthe sheets from the rotary electro-magnets.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing Witnesses.

yREGrINALD B. GERHARDT.

